Dual-mode electrical and chemical propulsion system for small spacecraft and CubeSats

Abstract

Dual mode engine for propelling spacecraft, including combustion chamber having flange end, open nozzle end, and enclosed chamber portion extending therebetween, propellant tank in fluidic communication with combustion chamber, electronic controller, power source operationally connected to electronic controller, and fluid flow motivator operationally connected to electronic controller and connected in fluidic communication with propellant tank. Engine has chemical propulsion portion with propellant inlet port operationally connected to combustion chamber and disposed adjacent flange end, ignition trigger electrode positioned in combustion chamber adjacent propellant inlet port and operationally connected to electronic controller and operationally connected to power source propellant inlet port fluidically connected to tank electric propulsion portion with two electrodes ionizing propellant positioned in combustion chamber adjacent nozzle end, plurality of attitude control thrusters operationally connected to electronic controller and in fluidic communication with propellant tank, and plurality of valves, each fluidically connected between attitude control thruster and propellant tank.

We claim: 
     
       1. A dual mode method for propelling a spacecraft, the method comprising:
 a first electric propulsion mode, further comprising:
 a) feeding a first predetermined quantity of a liquid propellant to a nozzle, wherein the nozzle defines an interelectrode space; 
 b) converting the liquid propellant in the interelectrode space to a plasma cloud; and 
 c) accelerating the plasma cloud by Lorentz force; and 
 a second propulsion mode, further comprising: 
 d) feeding a second predetermined quantity of the liquid propellant to a combustion chamber in fluidic communication with the nozzle; 
 e) igniting the liquid propellant in the combustion chamber to yield an exhaust cloud; and 
 f) expelling the exhaust cloud from the nozzle. 
 
 
     
     
       2. The dual mode method for propelling a spacecraft of  claim 1 , wherein step b) further comprises:
 b1) vaporizing the liquid propellant in the interelectrode space; and 
 b2) ionizing the liquid propellant in the interelectrode space. 
 
     
     
       3. The dual mode method for propelling a spacecraft of  claim 1 , wherein the liquid propellant is selected from the group consisting of AF-M315E, LMP-103S, hydrazine, and combinations thereof. 
     
     
       4. A dual mode thruster nozzle system for propelling a spacecraft, the dual mode thruster nozzle system comprising:
 a nozzle; 
 a pair of separated electrodes positioned in the nozzle and defining an ignition space therebetween; 
 a combustion chamber in fluidic communication with the nozzle; 
 a trigger electrode operationally connected to the combustion chamber; 
 a power source operationally connected to the pair of separated electrodes; 
 a power source operationally connected to the trigger electrode; 
 a liquid propellant reservoir in fluidic communication with the ignition space; 
 a liquid propellant reservoir in fluidic communication with the combustion chamber; 
 a fluid flow motivator connected in fluidic communication with the reservoir, the combustion chamber, and the ignition space; and 
 an electronic controller operationally corrected to the power source, to the respective electrodes, and to and to the fluid flow motivator. 
 
     
     
       5. The dual mode thruster nozzle system for propelling a spacecraft of  claim 4  wherein the nozzle is a ceramic. 
     
     
       6. The dual mode thruster nozzle system for propelling a spacecraft of  claim 5  wherein the ceramic is selected from the group consisting of alumina, boron nitride, and combinations thereof. 
     
     
       7. The dual mode thruster nozzle system for propelling a spacecraft of  claim 4  wherein the combustion chamber is made of polymer sheets made from fluoridated hydrocarbons. 
     
     
       8. The dual mode thruster nozzle system for propelling a spacecraft of  claim 4  wherein the liquid propellant is selected from the group consisting of AF-M315E, LMP-103S, hydrazine, and combinations thereof. 
     
     
       9. The dual mode thruster nozzle system for propelling a spacecraft of  claim 4  wherein the fluid flow motivator is selected from the group comprising a pump and a pressure source. 
     
     
       10. The dual mode thruster nozzle system for propelling a spacecraft of  claim 4  wherein the power source operationally connected to the pair of separated electrodes is the same power source operationally connected to the trigger electrode. 
     
     
       11. The dual mode thruster nozzle system for propelling a spacecraft of  claim 4  wherein the liquid propellant reservoir in fluidic communication with the ignition space and the liquid propellant reservoir in fluidic communication with the combustion chamber are unitary. 
     
     
       12. The dual mode thruster nozzle system for propelling a spacecraft of  claim 11  wherein the liquid propellant reservoir is connected in fluidic communication with the ignition space and with the combustion chamber are unitary through a single conduit. 
     
     
       13. A dual mode engine for propelling a spacecraft, comprising:
 a combustion chamber having a flange end, an open nozzle end, and an enclosed chamber portion extending therebetween; 
 a propellant tank in fluidic communication with the combustion chamber; 
 an electronic controller; 
 a power source operationally connected to the electronic controller; 
 a fluid flow motivator operationally connected to the electronic controller and connected in fluidic communication with the propellant tank; 
 a chemical propulsion portion further comprising:
 a propellant inlet port operationally connected to the combustion chamber and disposed adjacent the flange end; 
 an ignition trigger electrode positioned in the combustion chamber adjacent the propellant inlet port and operationally connected to the electronic controller and operationally connected to the power source; 
 wherein the propellant inlet port is fluidically connected to the propellant tank; 
 
 an electric propulsion portion, further comprising:
 at least two spaced electrodes for ionizing the propellant positioned in the combustion chamber adjacent the nozzle end; 
 a plurality of attitude control thrusters operationally connected to the electronic controller and in fluidic communication with the propellant tank; and 
 a plurality of respective valves, each respective valve fluidically connected between a respective attitude control thruster and the propellant tank; 
 wherein the propellant inlet port is fluidically connected to the propellant tank. 
 
 
     
     
       14. The dual mode thruster nozzle system for propelling a spacecraft of  claim 13  wherein the fluid flow motivator is selected from the group comprising a pump and a pressure source. 
     
     
       15. The dual mode thruster nozzle system for propelling a spacecraft of  claim 13  wherein the nozzle is a ceramic. 
     
     
       16. The dual mode thruster nozzle system for propelling a spacecraft of  claim 15  wherein the ceramic is selected from the group consisting of alumina, boron nitride, and combinations thereof. 
     
     
       17. The dual mode thruster nozzle system for propelling a spacecraft of  claim 13  wherein the combustion chamber is made of polymer sheets made from fluoridated hydrocarbons. 
     
     
       18. The dual mode thruster nozzle system for propelling a spacecraft of  claim 13  wherein the liquid propellant is selected from the group consisting of AF-M315E, LMP-103S, hydrazine, and combinations thereof.